Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Following is the example which uses getHeaderNames() method of HttpServletRequest to read the HTTP header information. This method returns an Enumeration that contains the header information associated with the current HTTP request.Once we have an Enumeration, we can loop down the Enumeration in the standard manner. We will use the hasMoreElements() method to determine when to stop and the nextElement() method to get the name of each parameter name. HTTP Header Request Example HTTP Header Request Example Header Name Header Value(s)
In general, the contents of a file are stored under Clob (TINYTEXT, TEXT, MEDIUMTEXT, LONGTEXT) datatype in MySQL database.JDBC provides support for the Clob datatype, to store the contents of a file in to a table in a database.The setCharacterStream() method of the PreparedStatement interface accepts an integer representing the index of the parameter and, a Reader object as a parameter.And sets the contents of the given reader object (file) as value to the parameter (place holder) in the specified index.Whenever you need to send very large text value you can use this method.Storing text file using JDBC:If you need to ... Read More
The asDoubleStream() method in the IntStream class returns a DoubleStream consisting of the elements of this stream, converted to double.The syntax is as followsDoubleStream asDoubleStream()First, create an IntStreamIntStream intStream = IntStream.of(20, 30, 40, 50, 60, 70, 80);After that, convert it to double with asDoubleStream() methodDoubleStream doubleStream = intStream.asDoubleStream();The following is an example to implement IntStream asDoubleStream() method in JavaExample Live Demoimport java.util.*; import java.util.stream.IntStream; import java.util.stream.DoubleStream; public class Demo { public static void main(String[] args) { IntStream intStream = IntStream.of(20, 30, 40, 50, 60, 70, 80); DoubleStream doubleStream = intStream.asDoubleStream(); doubleStream.forEach(System.out::println); } }Output20.0 30.0 40.0 50.0 60.0 70.0 80.0
The day of the year for a particular LocalDate can be obtained using the getDayOfYear() method in the LocalDate class in Java. This method requires no parameters and it returns the day of the year which can be in the range of 1 to 365 and also 366 for leap years.A program that demonstrates this is given as followsExample Live Demoimport java.time.*; public class Demo { public static void main(String[] args) { LocalDate ld = LocalDate.parse("2019-02-14"); System.out.println("The LocalDate is: " + ld); System.out.println("The day of the year is: " + ld.getDayOfYear()); ... Read More
GSON is java library, It is used to convert OBJECT to JSON and JSON to Object. Internally it going to work based on serialization and deserialization.This example demonstrates how to convert HASHAMP to JSON using GSON library.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code in build.gradle.apply plugin: 'com.android.application' android { compileSdkVersion 28 defaultConfig { applicationId "com.example.andy.myapplication" minSdkVersion 15 targetSdkVersion 28 versionCode ... Read More
To improve querying field in MongoDB, you need to use index. Let us create a collection with documents> db.improveQueryDemo.insertOne( ... { ... "PlayerDetails":[ ... {"PlayerName": "John", "PlayerGameScore": 5690}, ... {"PlayerName": "Carol", "PlayerGameScore": 2690}, ... ] ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5c9dbaf875e2eeda1d5c3670") }Following is the query to display all documents from a collection with the help of find() method> db.improveQueryDemo.find().pretty();This will produce the following output{ "_id" : ObjectId("5c9dbaf875e2eeda1d5c3670"), "PlayerDetails" : [ { "PlayerName" : "John", ... Read More
Create a Calendar instance and Date object −Calendar cal = Calendar.getInstance(); Date date = new Date(); cal.setTime(date);Now, create a HashMap and store Date value −LinkedHashMaphashMap = new LinkedHashMap(); hashMap.put("year", cal.get(Calendar.YEAR)); hashMap.put("month", cal.get(Calendar.MONTH)); hashMap.put("day", cal.get(Calendar.DAY_OF_MONTH));Example Live Demoimport java.util.Calendar; import java.util.Date; import java.util.LinkedHashMap; public class Demo { public static void main(String[] argv) { Calendar cal = Calendar.getInstance(); Date date = new Date(); System.out.println("Date = "+date); cal.setTime(date); LinkedHashMaphashMap = new LinkedHashMap(); hashMap.put("year", cal.get(Calendar.YEAR)); hashMap.put("month", cal.get(Calendar.MONTH)); hashMap.put("day", cal.get(Calendar.DAY_OF_MONTH)); ... Read More
You can use update along with lower() function for this. Let us first create a table −mysql> create table DemoTable ( Id varchar(100), StudentFirstName varchar(20), StudentLastName varchar(20), StudentCountryName varchar(10) ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('STU-101', 'John', 'Smith', 'US'); Query OK, 1 row affected (0.59 sec) mysql> insert into DemoTable values('STU-102', 'John', 'Doe', 'UK'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('STU-103', 'David', 'Miller', 'AUS'); Query OK, 1 row affected (0.19 sec)Following is the query to display all ... Read More
A byte array for the buffer can be obtained using the method array() in the class java.nio.ByteBuffer. If the returned array is modified, then the contents of the buffer are also similarly modified and vice versa. If the buffer is read-only, then the ReadOnlyBufferException is thrown.A program that demonstrates this is given as follows −Example Live Demoimport java.nio.*; import java.util.*; public class Demo { public static void main(String[] args) { int n = 5; try { ByteBuffer buffer = ByteBuffer.allocate(n); buffer.put((byte)1); buffer.put((byte)2); ... Read More
You can use length to query for documents where array size is greater than 1:db.yourCollectionName.find({$where:"this.yourArrayDocumentName.length > 1"}).pretty();To understand the above syntax, let us create a collection with some documents. The query is as follows to create a collection with documents:>db.arrayLengthGreaterThanOne.insertOne({"StudentName":"Larry", "StudentTechnicalSubje ct":["Java", "C", "C++"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c6d6c4c0c3d5054b766a76a") } >db.arrayLengthGreaterThanOne.insertOne({"StudentName":"Maxwell", "StudentTechnicalSu bject":["MongoDB"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c6d6c660c3d5054b766a76b") } >db.arrayLengthGreaterThanOne.insertOne({"StudentName":"Maxwell", "StudentTechnicalSu bject":["MySQL", "SQL Server", "PL/SQL"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c6d6c800c3d5054b766a76c") }Display all documents from a collection with the help of find() method. The query is as follows:> db.arrayLengthGreaterThanOne.find().pretty();The ... Read More